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%I #14 May 10 2020 04:32:08
%S 3,7,13,31,37,67,127,211,307,409,487,541,577,631,769,787,937,991,1009,
%T 1039,1117,1201,1291,1459,1471,1567,1777,1801,2251,2281,2467,2557,
%U 2647,2971,3037,3187,3259,3307,3559,3709,3847,3889,4441,4567,4801,4969,4987
%N Numbers that are both lucky numbers and Chen primes.
%H Amiram Eldar, <a href="/A117708/b117708.txt">Table of n, a(n) for n = 1..10000</a>
%t lst = Range[1, 5000, 2]; i = 2; While[ i <= (len = Length@lst) && (k = lst[[i]]) <= len, lst = Drop[lst, {k, len, k}]; i++ ]; chenQ[n_] := PrimeQ[n] && Plus @@ Last /@ FactorInteger[n + 2] < 3; Select[lst, chenQ@# &] (* _Robert G. Wilson v_, May 12 2006 *)
%Y Intersection of A000959 and A109611.
%Y Subsequence of A031157.
%K nonn
%O 1,1
%A _Jani Melik_, Apr 27 2006
%E Corrected and extended by _Robert G. Wilson v_, May 12 2006
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